#include <stdio.h>
#include <string.h>

int main()
{
	int n,i,j,len;
	scanf("%d",&n);
	char pass[50];
	getchar();
	gets(pass);
	len=strlen(pass);
	for(i=0;i<len;i++)
	{
		if(pass[i]=='z')
			pass[i]=pass[i]-26+n;
		else
			pass[i]=pass[i]+n;
	}
	puts(pass);
	return 0;
}